Pioneers of Nuclear Research Discovering atomic particles

W.K. Roentgen Found that some materials glowed in the presence of an energy form that could pass through cardboard. Called the energy “X-rays”

Fluorescing Minerals Some minerals produce light when hit by radiant energy (fluorescence) Fluorescence stops when the radiant energy is stopped

Henri Becquerel Do fluorescent minerals produce x-rays? Found that minerals can produce x-rays in the absence of radiant energy. Credited with the discovery of radiation

Marie Curie Worked with an ore of uranium (pitchblende) Found the amount of radiation emitted from the ore was higher than expected from the amount of uranium

Marie Curie Extracted two previously unknown elements Radium Polonium 1st person to receive two Nobel Prizes ever.

Rutherford’s 1899 Experiment Passed nuclear radiation through a magnetic field Demonstrated two types of radiation Alpha particles Beta particles

Old Plum Pudding Model of Atoms All the parts of an atom are stuck tightly together. Protons, neutrons and electrons are packed together.

Rutherford’s Gold Foil Experiment Shot radiation at a thin gold sheet. Expected the radiation to scatter widely as it squeezed between atoms

Rutherford’s Gold Foil Experiment Found that 2% of the radiation was deflected as expected. Instead, 98% passed straight through and a tiny amount shot back at the source Showed the nucleus is a small, positive area surrounded by mostly empty space.